Recently, a motorcycle driver had a problem, said that he bought a new electric spray car last year, only a few thousand kilometers, but now it is very difficult to use.

The main performance is large fuel consumption, driving hair, lack of power, accelerate black smoke.

I inquired about it, and found that the failure light on the dashboard had been turned on. The car was also carefully maintained at ordinary times, and the oil filter was changed as required.

Considering it is a new car, in the case of regular maintenance, there is little possibility of mechanical failure such as cylinder. So I suggested that the owner get a professional repairman to read the trouble code and see what the problem was.

In this way, the problem was finally solved through communication and maintenance. I also conveniently recorded the maintenance process and shared it today for reference to car owners and repairmen who encountered such problems.

His car uses the electronic jet system adopted by Zongshen Power. It uses the electronic jet detector to read the fault code and shows that the circuit voltage of the oxygen sensor is high.

The friends who often use the detector to repair the electric spray car all know that the equipment is only the equipment after all, he can only provide you with a general scope, assist you to judge, the final analysis of the fault site, or rely on the experience and technology of the repairman.

Judging from the fault phenomenon, the acceleration of this car gives off black smoke, which is obviously due to poor combustion of the mixture. Analyzing this fault, the possible causes are as follows:

One is the ignition problem, such as the occurrence of a broken fire, weak sparks and other circumstances, unable to effectively ignite the mixture, resulting in the mixture was not burned clean and discharged.

The second is the fault of the oxygen sensor, the signal transmitted to the ECU is not correct, so that the ECU judgment is wrong, control the fuel injector multi-injection, so that the mixture is too thick, a power cycle of the mixture can not burn completely.

Third, there is a problem with the intake system, which does not match the amount of fuel injection, resulting in too much mixture, which cannot be timely burned clean.

Since the detector indicates fault of oxygen sensor, check and analyze it around the sensor. For such problems, it is recommended that you read the fault code and check the data flow to see whether each part is working normally. If you find abnormal data, you can find the root cause.

By reviewing and analyzing the data flow, we found that the parameter of the oxygen sensor was normal, but it was unexpectedly found that the actual intake pressure value was 101Kpa, but this parameter deviated from the normal range.

Try the refueling door to increase the engine speed, the data did not change, more firmly the repairman's judgment.

That's a problem! Generally speaking, the normal intake pressure value in more than 40 kpa, if the difference between a dozen or twenty is reasonable, but suddenly differ by more than two times, that is obviously abnormal.

Failure of intake pressure may be caused by leakage of the intake system, or it may be caused by sensor blockage and corresponding circuit fault.

The data parameters obtained from the inspection process can be basically determined and the fault point should be located in the inlet pressure sensor.

On inspection, the car used a "triad sensor," a combination of intake temperature, intake pressure and throttle position sensors.

A second check of the perimeter found nothing unusual, so the repairman replaced a brand new three-in-one sensor and cleaned up the fault code.

After the new sensor is replaced, the data flow is read again. The inlet pressure value returns to normal. After the car owner tries riding, everything returns to normal and the fault is confirmed to have been eliminated.

According to my analysis, it is due to the problem of this sensor that the generated parameters are too high, making THE ECU mistakenly believe that the air volume of the cylinder increases.

In the case of increased air intake, if the oil injection volume remains unchanged, the mixture will inevitably be too thin. To prevent this, the control logic of ECU will increase the fuel injection pulse width and make the injector spray more oil.

But now we know that the signal was false, and that the intake was not actually increasing, and that the fuel injection must have resulted in the mixture being actually too thick, which led to the failure of this vehicle.